Sand-blast machine.



No. 708,880. I Patented Sept. 9, I902. F,.J HEIDEGER.

SAND BLAST MACHINE.

(Application filed. Oct. 8. 1901,]

LNo Model.)

INVENTOR m: norms Pzrzns co. pnoro-Llwo, wnsnmmon. u c.

UNITED STATES PATENT OFFICE.

FRANK J. HEIDEGER, OF WEST BRIDGEtVATER, PENNSYLVANIA.

SAN D-BLAST MACHINE.

SPECIFICATION formingpart' of Letters Patent No. 7 08,880, datedSeptember 9, 1902."

Application filed October 8. 1901. Serial No. 77,965. (No model.)

I be a full, clear, and exact description of the same, reference beingbad to the accompanying drawings, forming a part thereof.

Myinvention has relation to sand-blast machines, and particularly tomachines for frosting the interior surfaces of hollow glass articles,such as lamp globes, chimneys, &c.

The machine now usually employed for this purpose consists of astationary casing equipped with appliancesfor projecting a jet of sandinto its interior. The article to be frosted is supported upon ahorizontal spindle which is turned by hand, and the spindle in turn issupported upon a vertical shaft, so that as the work progresses thearticle may be swung around horizontallyto cause the sand jet toimpinge'successively against all parts of the surface to be frosted.Machines of this class are imperfect, unreliable, and slowin theperformance of the work intended. As the rotation and horizontalswinging of the articles is done entirely by hand the machine requiresthe constant attendance ofian operator, whose skill and judgment must beentirely depended on for the production of even accept-able results. Thehand rotation and horizontal movement of the article is necessarilylacking in the constancy and uniformity required for the production ofthe best results, sothat the frosting or grinding is rough and uneven.

The object of my invention is to overcome the defects and imperfectionsof the old-style machine and to provide a machine which will be entirelyautomatic, so that the application of the sand jet to the surfaces to befrosted will be regular, and thus insuring a degree of smoothness andperfection of finish not attainable by any other method or. apparatus.

The machine being entirely automatic performs its Work much morespeedily than other machines, and as it requires no attention while inoperation one man can easily control the operations of several machines,where is driven from a power-shaft. is provided with a hinged lid a, anda sealingair-tigh t.

strip, such as a tube of soft rubber b, is fastened to the innersurfaces of the walls of the casing below the lid to preventthe escapeof sand through the crevices or joint when the machine is in operation.

D designates an air-pipe leading from a source of supply of compressedair, and D is a sand-supply pipe leading from the bottom of a chest orhopper E below the casing A, containing a supply of dry sand. Thesand-pipe D is connected to and communicates with the air-pipe throughthe couplingjoint (Z, and the sand is sucked up by the vacuum created bythe air-blast and driven by the blast into the chestA through thenozzle-D The end of'theochest A through which the nozzle enters has alarge opening D to which is fitted a flexible diaphragm d.

The nozzle passes through the center of this diaphragm and is securedthereto by disks or washers 61 The diaphragm d is secured to theend ofthe chest A and the joints made chest is bent obliquely, so that when aglobe is arranged in position on the cage B the nozzle will point towardone side thereof.

The chest A is mounted on a vertical centralpivot A", so thatit may turnfreely in a horizontal direction to accommodate the article beingfrosted-to the positions required as the work progresses in order thatthe blast may be caused to impinge successivelyagainst all parts of theinterior surface of the article.

Attached to the bottom of the chest A is a segmental plate F, from theunder side of which depend the pins 9 g, arranged in a The jet pipe ornozzle. inside the quarter-circle and forming a rack for the en spindleI, mounted on bearings i t', drivenv from a suitable power-shaft.

Fig. 1 shows the position of the chestA when the work of frosting isabout to be started, the globe to be interiorly frosted being shown atK, inclosed within the cage B,with its open end toward the sand-nozzleand the latter projecting inside and pointing toward one side of theglobe. The lid of the chest is now closed, the pulleys O I started bymeans of a belt-shifter connected with the power-shaft, and the jetturned on by means of the valve-handle L on air-pipe D. The globe nowrotates automatically, while at every revolution of the spindle I thedog H engages with one of the pins g of the segmental plate F and movesthe chest A, and with it the spindle C, carrying the globe, the distancecorresponding to the intervals between the pins g. The movement of theglobe is in the arc of a circle and is, while intermittent, regular anduniform. When the chest A has been turned a quarter of a circle, thepins are all out of engagement with the dog H and the chest comes toastop, the globe having completed its travel in a circular direction andthe sand jet having impinged against every part of its inner surface andproduced a frosted finish perfectly uniform throughout and entirelydovoid'of roughness and irregularity necessarily consequent upon themanipulation of the globe in the ordinary manner. The sand driven intothe chest A is conveyed to the sand-hopper E by a pipe 6 and is usedover and over again. The air forced into the chest is carried awaythrough air-exhaust pipes M.

To shut 01f the blast automatically when the chest A has completed itsmovement, a stud M is attached to one of its sides, which at thetermination of each movement strikes the handle L and closes theair-valve, which is afterward opened by hand.

The pulley O is driven by any suitable means-as, for instance, a longbelt from an overhead power-shaft, which will not leave the pulley on aquarter-turn of the sand-chest.

Having described my invention, What I claim, and desire to secure byLetters Patent, 1s

1. In a sand-blast machine, the combination with a closed chest mountedon a vertical axis, a horizontal spindle journaled on said chest andhaving a work-holder and means for turning the chest on its axis and forrevolving the spindle, of a sand-nozzle projecting into the chest, anair-pipe to which said nozzle is connected, an air-valve on said pipe,and means for closing said valve automatically when the chest has turnedthe requisite distance.

2. In asan d-blast machine, the combination with a closed chest mountedon avertical axis, a horizontal spindle mounted on said chest and meansfor imparting a rotary motion to the spindle, of means for imparting arotary movement to the chest independently of the movement of thespindle, whereby the rates of motion of the spindle and chest may bevaried each independently of the other, substantially as described.

3. In asand-blast machine, the combination of a closed chest mounted ona vertical axis, a revolving spindle mounted on said chest and carryinga work-holder and means for imparting rotary motion to the chest and thespindle, of a sand-nozzle extending into said chest and a flexiblediaphragm attached to the chest and through which said nozzle projects,substantially as described.

4. In a sand-blast machine the combination with the airpipe D, a valveon said pipe and a valve-handle L, and automatically-rotating box orchest A, of means for automatically closing the air-valve, when the workis finished.

FRANK J. HEIDEGER.

Witnesses:

EDWARD KAYE, LnoPoLD BUssKo.

